The free offer of Azure App Service supports up to 10 free Web Apps with included storage and bandwidth. The included bandwidth had a daily quota of 165 MB per day across all Web Apps (10 Max) per region. This summed up to be 5GB of bandwidth per month per region. This quota was enforced on a daily basis and your Web Apps were suspended for the reminder of the day. You can have 1 web app (out of your max allowed 10) use up 165MB on a given day and this will result in all 10 web apps being suspended for the reminder of the day.

There are scenarios where your web app hosted in Free tier might encounter higher traffic on certain day of month, or you might want to perform certain testing which needs more than 165 MB of bandwidth for that day. Our current Free quota for bandwidth might not work well for these scenarios, hence we have recently made changes to the bandwidth quota of Free offering and relaxed it a bit. We will now be rolling over daily unused bandwidth to the next day’s quota until the end of a calendar month. First day of the new month will start over from 165 MB per day.

NOTE: It’s highly recommended that you use paid offerings for production and mission critical Web Apps.

The table below illustrates how bandwidth quota rollover is managed.

Initial Daily Limit = 165 MB

Limit for the day = Initial Daily Limit  + Rolled Over Quota

Per the above example, you will start January 1st with 165 MB of a daily quota and only used 65 MB for that day. 100 MB of unused data is rolled over to January 2nd which will now have daily limit of 265 MB (100 MB + 165 MB). On January 3rd your daily usage was 240 MB, which is over the limit of the day of 230 MB and hence you would start January 4th with daily limit of 165 MB. February 1st being the 1st day of new month will reset the roll over and you will start with 165 MB again.